1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
/******************************************************************************

                              Online C++ Compiler.
               Code, Compile, Run and Debug C++ program online.
Write your code in this editor and press "Run" button to compile and execute it.

*******************************************************************************/
#include <bits/stdc++.h>
using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    long long k;
    cin >> n >> k;
    vector<long long> w(n);
    long long il=0;
    for(int i=0;i<n;i++){
        cin>>w[i];
    }
    vector<long long> a = w;
    
    for(int i = 0; i < n; i++){
        long long p = a[i];
        for(int j = 0; j < n; j++){
            p = max(p, a[j] - k * abs(i - j));
        }
        w[i] = p;
    }
    for(int i = 0; i < n; i++){
        il += w[i] - a[i];
    }
    cout<<il;
}